Princes Street is a mess but it's our mess

From being the most desirable place to live in Britain, Edinburgh has become an unhappy urban sink - according to the polls. No doubt the indices for this latest survey, which put the Athens of the North well downstream of Cumbernauld, included traffic flow, new amenities for the young and property prices.

The sad truth is that, for the first time since 1971, property prices in the city have begun to fall. I first came to Edinburgh that year - though I don't think that had any direct impact on house sales, since I was in halls. Edinburgh then was a different place. No one ate or drank on the streets, largely because frostbite and jugs of sangria don't go well together and it's hard to see, let alone eat, your charred scallops on a herb rosti in the midst of a haar.

Much of that has gone and I have to say I quite liked the old Hoggish, Stevensonian Edinburgh. But the days when the hideous, fluorescent-lit Argyle House was the inner city's only grave architectural eyesore have also long gone. Edinburgh stands in some danger at the moment of losing its status as a world cultural heritage location. Unesco, which makes these designations, is alarmed at what it's seeing, both on paper and for real.

It's a cliche that the first sight of Edinburgh from Waverley Bridge is among the most impressive civic skyscapes in the world, a great core sample of human and architectural history. Then you spot the Scott Monument and the mess of Princes Street and it looks like a mythological city by Claude Lorrain overpainted by Andy Warhol in the right-hand corner.

The effect is actually more like bad dentistry, grey amalgam showing alongside unnatural white, chipped stumps next to hip-hop gold. But one of the limiting factors in civic architecture in Edinburgh since the war has been that bombing affected the city centre very little. (Don't mention this in Leith.)

Edinburgh's New Town was a planned urban space, but since then the city's architecture has been ad hoc and its silhouette, as first seen by Festival goers just after the war, was valued quite simply because it had survived unscathed, not because it was good or coherent. The Festival was an engine of postwar reconciliation and, given the state of Dresden and Coventry, it would have seemed in bad taste to complain.

It's 60 years since the Abercrombie Plan proposed a ring-route round the city and suggested a way of making Princes Street chime harmonically with the rest. That plan was chucked out and commerce won the day; a row of shops (Jenners notwithstanding, or now barely standing) that could be anywhere but for that view across the old castle moat.

There's no getting away from the fact that Princes Street is Scotland, an awkward muddle of beauty and circumstance, ugliness butted up against heritage, nobility and sharp practice forced to share a pavement. This is the street Renton sprints down in Trainspotting and you don't have to have read that book or seen that film to see that in the very centre of Edinburgh there are juxtapositions that underline its curiously divided nature.

It is often claimed that Edinburgh pushed its social problems out beyond the Abercrombie perimeter to keep the centre douce and proper. Every city tries to do that; Edinburgh might have tried, but it failed. As Hogg and Stevenson recognised, our split social nature is in the stones, glass and concrete. Unesco may not like it and if that makes you unhappy, you can always stay away. I say that every time I fight my way through the crowd.